I'm embarassed to bring this up again, because I seem to quote steven0461 too often--but, in something close to his words; "When you have eliminated the impossible, whatever remains is likely more improbable than an error in one of your impossibility proofs."
This is our monthly thread for collecting these little gems and pearls of wisdom, rationality-related quotes you've seen recently, or had stored in your quotesfile for ages, and which might be handy to link to in one of our discussions.